2003 Honda FCX -- Safety Performance

SAFETY PERFORMANCE

Safety measures for hydrogen and high-voltage electricity handling; omnidirectional collision safety performance

Safety measures for hydrogen and high-voltage electricity handling throughout the vehicle

The FCX features a package layout that positions the fuel cell system box under the floor and the high-pressure hydrogen tanks under the rear seat, completely isolating the cabin from all hydrogen and high-voltage lines. Hydrogen sensors are located throughout the vehicle to provide a warning in the unlikely event of a hydrogen leak. Should a hydrogen leak occur inside the fuel cell system box, a forced ventilation system is activated, and an automatic cut-off system closes the main stop valve on the hydrogen tank or appropriately located cut-off valves on the supply lines as necessary. The high-voltage lines are electrically isolated. If grounding occurs, a sensor sends a warning, and in the event of a collision a contact mechanism shuts down the source power line. Repeated floodwater testing and disaster tests carried out in tanks have confirmed a high level of safety and reliability.

Safety measures during hydrogen fueling

  • The filler receptacle provides firm contact with the filler nozzle, is equipped with a highly reliable filter, and employs a check valve with unitized construction to achieve an excellent hydrogen seal. This design prevents the mixing in of other gases or the errant connection of filler nozzles with the wrong filler pressure.
  • A grounding system is used to rid the vehicle of static electricity before fueling.The safety design locates the hydrogen refuelling lid release inside the grounding lid, so the grounding lid must be opened first before the refuelling lid can be opened.

Frame designed to withstand collisions from multiple directions

In addition to incorporating advanced technologies developed by Honda for all its automobiles, including dual front airbags and an energy-absorbing body structure, the fuel cell vehicle pursues a level of collision safety performance all its own. Besides protecting vehicle occupants from collisions from the front, sides, and rear, the FCX also exhibits an outstanding level of safety performance to protect the fuel cell system and high-pressure hydrogen tanks from impacts and the effects of body deformation in a crash.

Photos: Collision testing of car built to U.S. specifications

A large-cross-section, straight configuration from the front frame to the floor frame is bolstered by outriggers and a cross-member that extends all the way out to the side sills. The front frame has an impact-absorbing construction to reduce the force of the impact on the cabin area in a frontal collision. The outriggers effectively absorb the impact of a side collision to minimize the effect on the cabin and fuel cell system.

Two-stage construction of high-strength rear aluminum sub-frame and rear frame protects high-pressure hydrogen fuel tank

The lightweight, rigid rear sub-frame with extruded aluminum members is attached to the rear frame in a vertical two-stage construction. In a rear collision, the back part of the rear frame first effectively absorbs the impact. Then the two-stage construction of the sub-frame and rear frame restrains the impact's force to protect the high-pressure hydrogen tanks.